XWEM is an attempt to built ideal desktop. It is not a secret that Emacs is most powerfull environ one has used, but it leaks some real integration to desktop because it can't have control over every thing. XWEM will try to break this barrier.

I've just done system tray support in xwem. It uses extended XEMBED protocol which allows any dock in tray to run Emacs Lisp. xwem-minibuffer is used as system tray, so screen does not lost any area. I also included few examples in C, which shows you how to use xwem-tray. They taken from matchbox project and moddified a little. There is screenshot of it - http://lgarc.narod.ru/xwem/xwem-screen1.png